Thursday, June 01, 2006

An alternative-energy project at Western Washington University would power cars with natural gas harvested from cow manure.

Students at the state university's Vehicle Research Institute have developed a scrubber that removes the corrosive chemicals from the gases released by manure so it can power a natural-gas car.

Eric Leonhardt, director of the institute, said the fuel, which he calls "biomethane," is less flammable than gasoline and produces fewer greenhouse gases than manure left to decompose naturally in fields.

He estimates that the natural gas would cost about half the current price of gasoline to produce, but emphasizes that that is not the real benefit of cow power.

"If we can get farmers to put in anaerobic digesters, that's going to be the environmental impact," he said. "The gas is really an aside. The real impact is getting manure out of the water supply."

Killing two birds with one turd. Marvelous!

I chuckled when I saw this yesterday morning on the local AM broadcast leading up to Katie's 3-hour farewell tour. Little did I understand the seriousness of it all:

Only one farm in Washington has started turning its cow manure into natural gas, although the process is catching on more quickly in some other states where utility companies are helping farmers buy anaerobic digesters.

An anaerobic digester on Darryl Vander Haak's dairy farm in Lynden processes manure from about 1,000 cows into electricity to sell to Puget Sound Energy. At full capacity, the digester can produce enough energy to power 180 homes.

The raw biogas contains highly corrosive hydrogen sulfide, so it must be processed before it can be used in motor vehicles that run on natural gas.

Leonhardt says his institute is working on creating a commercially viable bioscrubber to turn that idea into a reality.

One of Leonhardt's students, Matt Wilson, said the scrubber they have developed from PVC pipe and spare parts removes both hydrogen sulfide and carbon dioxide from methane gas. The gas is then compressed before it can be pumped into a special natural-gas-powered car.

Waste produced by 15 cows has been enough to run the institute's natural-gas car for 250 to 300 miles, Wilson said.